Caerphilly county borough lies in the South Wales Valleys bounded in the south by the county boroughs of Cardiff and Newport, and by Powys and the Brecon Beacons National Park in the north. The habitats of the county borough are varied, including species-rich grasslands (rhos pasture), fragments of ancient woodland, hedgerows, rivers and ponds. Important and/or rare species include greater horseshoe bat and great crested newt, but other species such as the Cornish moneywort and peregrine falcon, are considered to be important locally.

The Caerphilly Biodiversity Partnership comprises over 40 organisations, including Natural Resources Wales, Caerphilly CBC and local wildlife groups, such as the Ruperra Conservation Trust. The partnership meets every 3 months at the Ynys Hywel Centre in the Sirhowy Valley Country Park.

Current Local Biodiversity Action Plan projects include a Biodiversity Conservation Programme of practical tasks and survey training, awareness-raising events, in particular 'Go Wild' and the Caerphilly in Bloom wildlife garden category, and surveys for great crested newt, brown hare and a very successful public participation survey of house nesting birds.